School of Optometry and Vision Science, University of New South Wales, Sydney, Australia.
The Kirby Institute, University of New South Wales, Sydney, Australia.
Clin Exp Optom. 2022 Mar;105(2):214-221. doi: 10.1080/08164622.2021.1971050. Epub 2021 Sep 30.
Optometrists have been advised to wear face masks during the COVID-19 pandemic. This study examined whether face masks were equally protective against transmission of microbes.
The aim of the current study was to examine the ability of face masks to reduce transmission of microbes in aerosols and during speech.
Different face masks, surgical, medical 3-ply and cloth masks with different layers were used. The masks were tested under the ASTM standard F2101-1 to measure their ability to reduce the transmission of aerosolised . Bacterial cells in different sized aerosols were captured on agar plates. The ability of masks to reduce the transmission of bacteria during speech over 30 cm was measured. Bacteria were captured in masks or on agar plates at a distance of 30 cm during the speech.
All masks reduced the transmission of aerosolised (p ≤ 0.007). The medical 3-ply and cloth masks with three layers reduced the transmission of aerosols (3.3 μm) by 98% and surgical and seven-layer masks reduced this by 100%. An antibacterial silver mask showed significantly greater transmission of in aerosols of 4.7 μm (16 ± 6 cells) and 3.3 μm (122 ± 66 cells) compared to all other masks (0-3 cells and 0-15 cells, respectively; p ≤ 0.016). Surgical and three-layer masks had significantly worse filtration of 1.1 μm aerosols than for other aerosol sizes. Wearing a mask reduced the transmission of bacteria during speech, but the inner surface of these masks became contaminated with 528-3060 bacterial cells.
Face masks effectively reduce the transmission of microbes in laboratory tests. Face masks made with seven layers were very effective at stopping transmission of in all aerosol particle sizes. However, face masks become rapidly contaminated during wear. If masks are to be re-used, they should be regularly replaced or appropriately washed.
在 COVID-19 大流行期间，视光师被建议佩戴口罩。本研究旨在检验口罩是否同样能预防微生物传播。
本研究旨在检验口罩在减少气溶胶和言语传播过程中微生物传播的能力。
使用不同的口罩，包括外科口罩、医用三层口罩和不同层数的布口罩。根据 ASTM 标准 F2101-1 测试口罩减少气溶胶化 传播的能力。将不同大小气溶胶中的细菌细胞捕获在琼脂平板上。测量口罩在 30cm 距离处减少言语过程中细菌传播的能力。在说话时，将细菌捕获在口罩上或 30cm 处的琼脂平板上。
所有口罩均减少了气溶胶化 传播（p≤0.007）。医用三层口罩和三层布口罩减少了 3.3μm 气溶胶的传播（98%），而外科口罩和七层口罩则将其完全阻断。与所有其他口罩相比，具有抗菌银的口罩在 4.7μm（16±6 个细胞）和 3.3μm（122±66 个细胞）的气溶胶中显示出显著更高的 传播（0-3 个细胞和 0-15 个细胞，分别；p≤0.016）。外科口罩和三层口罩对 1.1μm 气溶胶的过滤效果明显差于其他气溶胶尺寸。佩戴口罩可减少言语过程中的细菌传播，但这些口罩的内表面会被污染，含有 528-3060 个细菌细胞。
口罩在实验室测试中有效减少微生物的传播。具有七层的口罩在阻止所有气溶胶颗粒大小的 传播方面非常有效。然而，口罩在佩戴过程中会迅速被污染。如果口罩要重复使用，应定期更换或适当清洗。
